Liquid crystal displays (LCD) have been widely applied in electrical products due to the rapid progress of optical and semiconductor technologies. With their advantages of high image quality, compact size, light weight, low driving voltage, low power consumption and various applications, LCDs have been introduced into portable computers, mobile phones, personal digital assistants and color televisions and are becoming the mainstream display apparatus.
The LCD needs a color filter (CF) disposed therein to be colorful. A liquid crystal panel of the LCD can change the voltage to control the orientation of liquid crystal molecules in a liquid crystal layer. The liquid crystal molecules in the liquid crystal layer can switch the light provided from a backlight module to pass through or not. The light from the backlight module passes through the color filter to form colorful light. Currently, the CF substrate in the LCD includes a black matrix on a transparent substrate, a color filter film with red, green and blue colors formed in the black matrix and an ITO electrode on the color filter film.
Since the LCD has a major disadvantage of its narrow viewing angle, several techniques for increasing the view angle have been developed. Among the techniques, the ITO electrode of the CF substrate is patterned to form a plurality of electrode regions, thereby forming the multi-domain electric field to control the orientation of liquid crystal molecules and to increase the view angle.
Refer to FIG. 1A and FIG. 1B. FIG. 1A is a partial top view showing a conventional ITO electrode on a substrate, and FIG. 1B is a cross-sectional view along the cross-sectional line A-A′ shown in FIG. 1A. However, when the ITO electrode 910 is patterned to form on a substrate 930 with a certain stereo-structure 920, such as the color filter film, there may be an undercut structure formed at the edge of the stereo-structure 920, and thus the ITO electrode 910 cuts off at the edge of the stereo-structure 920. Therefore, a portion of the ITO electrode 910 may not be conductive, and the liquid crystal panel of the LCD cannot form the multi-domain electric field to control the orientation of liquid crystal molecules.